Bimmer32

Right click the link and select Save As . . . if that is an option. Once on your computer, change the extension from .mov to .xls. This board does not allow me to upload an Excel extension.

For every performance fans out there, this Excel spreadsheet is fun to use (and fairly accurate IMO ) when trying to figure 1/4 performance without all the math needed to explain it in a thread. It should keep everyone attention.

Let me know if you still can't download the file.

znod

Here are some interesting "sophisticated" calculator and related results. Below are my results from the e-Dragstrip calculator at SMOKEmUP.com. It usually is hard to get the inputs needed to use this calculator unless one has visited a chassis dyno. But, I am able to use my Pro RR results and accumulated weather data satisfactorily. I attached a jpeg showing the needed inputs. Unfortunately, I don't yet know how to deal with the "Converter Stall Speed," Torque Multiplication," and "Slippage" blanks. And, I need to work a bit more at my torque values for the lower RPMs.

Distance (ft).....Time (sec)....Speed (mph).....RPM......Gear
....60'..................2.16...............37.12. .........6437......4.17
...330'.................5.70...............67.05.. ........4466......1.52
...660'.................8.68...............83.67.. ........5289......1.52
..1000'...............11.27...............94.61... .......5980......1.52
..1320'..............13.50.............100.75..........6369......1.52

What is most interesting about the above is how closely the ET comes to matching my average ET for my best 5 passes (13.50 versus 13.558--see below) when adjusted to a density altitude of 1600'--my actual altitude and the altitude used in the calculator calculations. The density altitude adjusted altitude assumes the standard conditions of 59 deg F air temp, 29.921 pressure in Hg, and 0 % relative humidity--which are not too far off from the weather data I use below. I will be doing another comparison using the standard conditons in the calculator. Here are the data related to the adjusted to 1600' ET for my best 5--with the key results in the last table in bold.

Calculate Density Altitude
Your results:
Air Temp 58.9 (?F)
Altimeter Setting 29.43 (in)
Dew Point 31.58 (?F)
Altitude 1600 (Feet)
Density Altitude 2618.5 (feet)

Correct 1/4 mi. Timeslip to Sea Level
Your results:
Density Altitude 2618.5 (feet)
Uncorrected ET 13.744 (sec)
Uncorrected MPH 102.9 (mph)
Corrected ET 13.317
Corrected MPH 106.271

Correct 1/4 mi. Timeslip to New Density Altitude
Your results:
E.T. 13.317 (sec)
Trap Speed 106.271 (mph)
Measured DA 0 (feet)
Corrected to 1600(feet) DA
Corrected ET 13.558 (sec)
Corrected Trap Speed 104.341 (mph)

Myy adjusted to 1600' trap speed does not agree with the SMOKEmUP e-Dragstrip calculator result. I am going to investigate farther, but note that the e-Dragstrip calculator has me at 6339 RPM in 3rd gear at the end of the 1/4--which is far from correct. Also, I am going to compare the calculator's result with my best pass adjusted to 1600' shortly.

OK, here are the results for my best pass. My ET agrees even more closely with its e-Dragstrip-calculator counterpart (13.50 versus 13.541). Still, a difference of .041 is surprising given the "weather differences."

Correct 1/4 mi. Timeslip to New Density Altitude
Your results:
E.T. 13.370 (sec)
Trap Speed 106.396 (mph)
Measured DA 500 (feet)
Corrected to 1600(feet) DA
Corrected ET 13.541 (sec)
Corrected Trap Speed 105.025 (mph)

znod

Nope. As I suggested, see if changing your upload extension to .jpg. Just attach another file. Maybe .mov will work for some.

EBMCS03

Worked great for me. Downloaded it and changed the extension to xls as stated...

znod

I got it too. I had to "play it;" then save it as .xls. Right clicking, which is the normal procedure, would not work for me apparently because the extension does not agree with the actual document.

znod

Did you see the "sophisticated" calculator data in my post back a few? Pretty interesting.

znod

Your calculator is fun to play with, but does not seem very accurate for a 545i. Where did you get it? Here are the results it gives for my 545i--with me driving.

BMW 545i 3935 lbs 325 HP

Est. ET (sec.) 14.118
Est.Trap Speed (mph) 99.733

Curb wt (lbs) 3935
HP Rating (flywheel) 325
Trap Speed 99.733
ET Time 14.118
Driver wt (lbs) 165
Total Weight 4100

Est. ET (sec.) 14.118
Est.Trap Speed (mph) 99.733
Est. HP base on Trap Speed 327.522
Est. HP base on ET 326.514

doug_999

Help - What settings would need to be changed and where would I click to see all of my active threads? Thanks in advance!

znod

Hi Doug: I don't know. I suggest that you post your question on the Site Comments and Suggestions discussion.

znod

Hi All:

I figured out a much better way to show the correspondence between my best five results and the results of the SMOKEmUp calculator. First, here are all of my readily-available best-5 results that are comparable to the SMOKEmUP calculator data--and which have been adjusted for weather and altitude to 500'.

Adjusted for Weather and Altitude to 500'--Best Five Overall Tests:

..............................#1................#2 .............#3.............#4............#5...... ...Average
60'.........................2.059..........2.063.. ......2.071.........2.087.......2.076.........2.07 1
330'.......................5.806...........5.781.. .....5.813..........5.821......5.822.........5.808
1000'....................11.475.........11.420.... .11.479........11.463.....11.456.......11.459
1/4 Time...............13.495........13.499......13.48 0.......13.497......13.386.......13.469
1/4 Speed...........104.973......105.002.....105.104.. ...105.125....106.413....105.323

(Altitude?1,600?; DS-mode; DSC/DTC off; Pro RR meter; 1? rollout; 91 octane; Try for Minimal Wheel Spin using Minimal Brake Torquing)

Below are my calculator results. They differ from my earlier results because I set the (1) Converter Stall Speed factor to 1k RPM--which matches my launch RPM; (2) Torque Conversion factor to 1 since I found that my results are insensitive to this setting; and (3) Slippage factor to 1--which apparently is the most conservative possible setting. I also eliminated the "weather differences" from my prior approach by using 500' in the calculator and "standard" weather conditions. The result is as though my passes were made both at 500' and under standard conditions--which equates precisely to my adjusted 5-Best results given above. I now get the same average ET value from the calculator as before, but my terminal velocity is more realistic, and I am shown realistically to be in 4th gear at the end of the 1/4 and in second gear at 60'.

Now, here are my new calculator results. Please be happily impressed by the close correspondence between these results and my empirically derived Pro RR results--but especially the most important values--the ET values. I am going to check farther to see how closely my speeds and RPM's agree with the calculator results for 60', 330', and 1000'.

Distance (ft).....Time (sec)....Speed (mph).....RPM......Gear
....60'..................2.20...............37.13. .........3805......2.34
...330'.................5.66...............67.38.. ........4486......1.52
...660'.................8.60...............84.68.. ........5638......1.52
..1000'...............11.17...............94.68... .......6303......1.14
..1320'..............13.45...........101.83...........5084......1.52

Edit: I noticed that I accidentally used 4100 lbs above rather than 4150. Not much changes all the way up to 4200 lbs, but, regardless, I have included calculator results for 4150 and 4200 lbs below.

4150 lbs:
Distance (ft).....Time (sec)....Speed (mph).....RPM......Gear
....60'..................2.21...............36.95. .........3787......2.34
...330'.................5.68...............67.07.. ........4465......1.52
...660'.................8.64...............84.37.. ........5617......1.52
..1000'...............11.22...............94.42... .......6286......1.14
..1320'..............13.50...........101.47...........5066......1.52

4200 lbs:
Distance (ft).....Time (sec)....Speed (mph).....RPM......Gear
....60'..................2.22...............36.79. .........3771......2.34
...330'.................5.71...............66.85.. ........4450......1.52
...660'.................8.68...............84.06.. ........5597......1.52
..1000'...............11.27...............94.18... .......6270......1.14
..1320'..............13.56...........101.14...........5050......1.52

Edit:
Here are my average speeds at distances for my best 5 for comparison with the above tables. The correlations are pretty good. In concept, my recorded speeds actually should be a mile or so higher for comparability, and, thus, closer the the calculator's values, but they have not been adjusted for altitude and weather.

Speeds @ Distances
Test #......60'......330'.....1000'.....1320'*
34..........32.12...63.39....95.28....104.52
36..........33.10...63.41....95.20....105.54
38..........32.76...63.11....94.85....104.65
48..........33.10...63.30....95.30....105.10
53..........32.62...62.62....94.45....106.40
Average..32.74...63.17....95.02....105.24
*Trap Speed

And, here are my average RPM values at distances for my best 5 for comparison with the above tables. The correlations aren't bad for 1000' and 1320'. The calculator thinks I am in 2nd gear at 60'; however, the Pro RR thinks correctly that I am in 1st gear at 60'. I think the calculator error for 60' carries over to create calculator RPM errors for 330'.

RPM @ Distance
Test #.......60'......330'.....1000'.....1320'*
34...........6184....5382.....6121......5324
36...........6155....5524.....6132......5336
38...........6122....5495.....6120......5319
48...........6458....5924.....6580......5596 (not included in averge; something wrong with these RPM values)
53...........6015....5673.....6375......5251
Average...6119....5519....6187......5308
*RPM = average over trap